Roll adjustment system

ABSTRACT

A system may comprise a frame, a pair of rolls with each of the rolls comprising a roll body having opposite ends and a circumferential surface, a plurality of teeth being formed on the circumferential surface, and at least a portion of the circumferential surface being electrically conductive. The roll may also have a roll shaft having end portions extending from the roll body, with each of the end portions extending from one of the ends of the roll body. The system may also comprise roll supports configured to support the rolls on the frame in a manner such that at least one of the rolls is movable to adjust a separation gap between the rolls, a detection apparatus configured to detect contact between the rolls, and a signaling apparatus configured to produce a signal indicating a change in electrical potential is detected by the detection apparatus.

REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of U.S. patent applicationSer. No. 14/821,936, filed Aug. 10, 2015, which is hereby incorporatedby reference in its entirety.

BACKGROUND

Field

The present disclosure relates to adjustable rolls such as can be usedon grinding equipment and more particularly pertains to a new rolladjustment system for detecting the zero point for a movable roll moresafely and accurately.

Description of the Prior Art

In machinery utilizing rolls or rollers (the terms being usedinterchangeably in this description), such as grain processingapparatus, the rolls typically have teeth formed on the substantiallycylindrical outer surface to grind or substantially pulverize the grainparticles passing between a pair of the rolls, or multiple pairs ofrolls arranged in series with respect to each other. The separation gapbetween the pair of rolls is very important to achieving a groundproduct that has the desired particle size and consistency. However, theseparation gap needs to be changed or adjusted from time to time due to,for example, a desired change in the character of the output product,loss of the proper position adjustment of the rolls, wear on the partsof the apparatus (e.g., the teeth on the rolls), as well as otherreasons.

For example, during startup of the grinding apparatus, the rollseparation gap is typically adjusted to a suitable or desired setting.To do so, a proper zero location or point for the movable roll must bedetermined from which the separation gap may be measured. The zerolocation may be defined as the position of the movable roll in which themovable and stationary rolls are in contact with each other, or at leastthe ends of the rolls are in contact with each other, such that therotation axes of the rolls are presumed to be substantially parallel.

The zero location is thus determined by detecting when the rolls justcontact each other to establish a zero point. Then adjustment of theseparation gap may be made between the rolls based upon the zero point.In some apparatus, the separation gap between the rolls may be adjustedby moving the position of the bearings supporting the ends of themovable roll. Each of these bearings may include a spring-loaded mountin which a threaded bolt or rod is used to adjust the position of thebearing of the movable roll with respect to the other (stationary) roll.Rotation of the bolt or rod moves the bearing, and the corresponding endof the movable roll, closer to or further away from the stationary rolldepending upon the direction of rotation of the bolt or rod.

The process of adjusting the separation gap between the rolls mayinitially entail operating the apparatus so that the rolls rotate in aspaced relationship of (usually) unknown separation gap, and then movingthe rotating movable roll relatively closer to the rotating stationaryroll until contact is detected between the movable and stationary rolls.The point at which contact is detected is considered to be the zeropoint for the movable roll.

Accurately detecting the initial point of contact between the rotatingrolls can be difficult. One way of detecting contact (or imminentcontact) requires the insertion of a feeler gauge between the movableand stationary rolls, and when a feeler gauge can no longer be insertedbetween the rolls, contact between the rolls is detected and the zeropoint is identified. Another way of detecting contact requires theoperator to listen for the sound produced by the initial contact of therotating rolls as the moving roll moves toward the stationary roll, tothereby identify the zero point.

SUMMARY

The present disclosure relates to a system comprising a frame, a pair ofrolls including a first roll and a second roll. The rolls may comprise aroll body having opposite ends and a circumferential surface, aplurality of teeth formed on the circumferential surface, and at least aportion of the circumferential surface being electrically conductive.The rolls may also comprise a roll shaft having end portions extendingfrom the roll body with each of the end portions extending from one ofthe ends of the roll body. Roll supports may be configured to supportthe rolls on the frame in a manner such that at least one of the rollsis movable to adjust a separation gap between the rolls. The system mayalso include a detection apparatus configured to detect contact betweenthe rolls, and a signaling apparatus configured to produce a signal whenthe detection apparatus detects contact between the rolls.

In another aspect, the disclosure relates to a system comprising aframe, a pair of rolls with the rolls including a first roll and asecond roll. Each of the rolls has a circumferential surface, aplurality of teeth being formed on the circumferential surface, and atleast a portion of the circumferential surface being electricallyconductive. The system may also comprise roll supports configured tosupport the rolls on the frame in a manner such that at least one of therolls is movable to adjust a separation gap between the rolls, and adetection apparatus configured to detect contact between the rolls. Thesystem may also comprise a signaling apparatus configured to produce asignal when the detection apparatus detects contact between the rolls,and an adjustment apparatus configured to receive the signal from thesignaling apparatus and change movement of one of the rolls with respectto the other of the rolls.

There has thus been outlined, rather broadly, some of the more importantelements of the disclosure in order that the detailed descriptionthereof that follows may be better understood, and in order that thepresent contribution to the art may be better appreciated. There areadditional elements of the disclosure that will be described hereinafterand which will form the subject matter of the claims appended hereto.

In this respect, before explaining at least one embodiment orimplementation in greater detail, it is to be understood that the scopeof the disclosure is not limited in its application to the details ofconstruction and to the arrangements of the components, and theparticulars of the steps, set forth in the following description orillustrated in the drawings. The disclosure is capable of otherembodiments and implementations and is thus capable of being practicedand carried out in various ways. Also, it is to be understood that thephraseology and terminology employed herein are for the purpose ofdescription and should not be regarded as limiting.

As such, those skilled in the art will appreciate that the conception,upon which this disclosure is based, may readily be utilized as a basisfor the designing of other structures, methods and systems for carryingout the several purposes of the present disclosure. It is important,therefore, that the claims be regarded as including such equivalentconstructions insofar as they do not depart from the spirit and scope ofthe present disclosure.

The advantages of the various embodiments of the present disclosure,along with the various features of novelty that characterize thedisclosure, are disclosed in the following descriptive matter andaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure will be better understood and when consideration is givento the drawings and the detailed description which follows. Suchdescription makes reference to the annexed drawings wherein:

FIG. 1 is a schematic perspective view of an illustrative grindingapparatus suitable for employing the new roll adjustment systemaccording to the present disclosure.

FIG. 2 is a schematic side view of a grinding apparatus with the newroll adjustment system, according to an illustrative embodiment.

FIG. 3A is a schematic sectional view of the grinding apparatus with theroll adjustment system, according to an illustrative embodiment, withone end of the movable roll in a zero position with respect to thestationary roll and thus completing a circuit.

FIG. 3B is a schematic sectional view of the grinding apparatus with theroll adjustment system, according to an illustrative embodiment, withboth ends of the movable roll in a zero position with respect to thestationary roll and thus completing a circuit.

FIG. 3C is a schematic sectional view of the grinding apparatus with theroll adjustment system, according to an illustrative embodiment, withthe movable roll separated by a uniform separation gap from thestationary roll and thus not completing the circuit.

FIG. 4 is a perspective view of a portion of the system including an endportion of the first roll and the respective roll support with elementsof the isolating assembly.

FIG. 5 is a schematic diagram of elements of an embodiment of thesystem.

FIG. 6 is a schematic side view of an embodiment of an illustrativegrinding apparatus.

FIG. 7 is a schematic enlarged view of a portion of the side of theillustrative embodiment of FIG. 6.

FIG. 8 is a schematic enlarged view of a portion of the top of theillustrative embodiment of FIG. 6.

FIG. 9 is a schematic end view of the illustrative embodiment of FIG. 6.

FIG. 10 is a schematic enlarged view of a portion of the end of theillustrative embodiment shown in FIG. 9.

FIG. 11 is a schematic diagram of elements of an embodiment of thesystem.

DETAILED DESCRIPTION

With reference now to the drawings, and in particular to FIGS. 1 through10 thereof, a new roll adjustment system embodying the principles andconcepts of the disclosed subject matter will be described.

The applicants have recognized that problems exist with the knowntechniques for zeroing, or finding the zero location, for a movable rollof a pair of rolls of an apparatus in that the techniques may not bevery accurate in establishing a zero point and may be hazardous to theoperator attempting to perform the zeroing operation. For example, usingthe technique of listening for the sound of the initial contact of therolls may be difficult to perform in the typically loud environment of amilling facility, especially for inexperienced machine operators, and ahard collision between the rolls which damages the teeth on the rollsmay result. Even when the technique is performed by an experiencedoperator able to reliably detect the initial contact between thespinning rolls, the technique imposes additional wear to the rolls overthe long term that is likely to shorten the useful life of the teeth onthe roll. Using the technique of insertion of a feeler gauge between therotating and moving rolls can also be hazardous to the operator.

Further, the applicants have recognized that due to variations in theframe structure of the apparatus and the rolls themselves, it ispreferable to adjust the ends of the movable roll independently of eachother to establish a zero point for each end rather than moving bothends at the same time. Then adjustment of the separation gap may be madebetween the corresponding ends of the rolls based upon those zeropoints. The process of adjusting the separation gap between the rollsmay include operating the rolls rotate in a spaced relationship and thenmoving one end of the rotating movable roll relatively closer to therotating stationary roll until contact is detected between the end ofthe movable roll and the stationary roll. The point at which contact isdetected is considered to be the zero point for that end of the movableroll, and may be repeated for the opposite end of the movable roll withrespect to the stationary roll.

In light of these problems, the applicants have developed a system andmethod for detecting the zero point for a pair of rolls in a manner thatis believed to be more easily and accurately (and safely) performed evenby those with relatively less operational experience. In some aspects ofthe disclosure, the pair of rolls of the apparatus effectively functionas an electrical switch to complete a circuit, and completion of thecircuit may be used to signal and inform the operator that the rollshave contacted each other and the movable roll is at the zero locationor point relative to the stationary roll. An electrical charge may beapplied to one of the rolls and the other roll is electrically isolatedfrom the charged roll (and may also be isolated from the frame). Aconductor is electrically connected to the isolated roll so that whencontact is made between the rolls (e.g., between the movable and thestationary rolls) a circuit is completed and current may flow betweenthe rolls. The completion of the circuit may provide a means forsignaling or indicating that contact between the rolls has occurred,without requiring the operator to hear the contact or insert an objectsuch as a feeler gauge. The completion of the contact detecting circuitcan be performed while the rolls are rotating or not rotating. Thecompletion of the circuit and the resulting current flow may also beemployed to provide a signal to a controller or computer or otherprocessor indicating that contact between the rolls has been made, whichin turn may be used to control devices that automatically adjust theposition of the movable roll to achieve the separation gap required fora particular task or operation. In this way, adjustment of the positionof the movable roll, and therefore the separation gap, may be performedautomatically rather by than the aforementioned manual techniques.

In some aspects, the disclosure relates to a system 10 which may have asits purpose the grinding or crushing or otherwise processing a material,typically a particulate material which may include various grains orother foodstuffs. Such apparatus may include one or more stages ofgrinding or processing that progressively change the grain, such as bygrinding the particles into smaller and smaller sizes. It should berecognized that while the illustrative embodiments of this disclosureprimarily relate to apparatus for processing particles into smallerparticles, aspects of the concept may be applied to other apparatusemploying rotatable objects in which a spacing therebetween isadjustable from a zero point at which the objects are in contact.

Illustrative systems 10 that may be suitable for the implementation ofthe aspects of the disclosure may include a frame 12 and a pair of rolls14, 16 mounted on the frame in a manner permitting rotation of therolls. While suitable systems may include more than one pair of therolls, and each pair of rolls may have a different spacing than theother pairs in order to create progressively finer product passingthrough the system. For the purposes of this description a single pairof rolls will be described with the understanding that additional pairsof rolls of a system may utilize multiple similar or identical elements.The pair of rolls may include a first roll 14 and a second roll 16 thatare generally oriented substantially parallel to each other and mayrotate in the same or opposite rotational directions. Each of the rolls14, 16 may include a roll body 18 with opposite ends 20, 21 and acircumferential surface 22 extending between the ends 20, 21. Typicallythe circumferential surface 22 is substantially cylindrical in shape,and includes a plurality of teeth 24 that are formed on thecircumferential surface which protrude outwardly to some degree from thesurface 22 and are effective for the grinding or otherwise processingthe material moving through the system 10. In some embodiments the teeth24 extend from the first end 20 to the second end 21, and may besubstantially straight between the opposite ends 20, 21, and may besubstantially continuous between the ends, although the particular formof the teeth is not necessarily critical to the disclosure and otherteeth configurations may be employed.

Each of the rolls 14, 16 may also include a roll shaft 26 that mayextend through the roll body 18 and have end portions 28 which areexposed and extend from the opposite ends 20, 21 of the roll body. Theend portions 28 of the roll shaft 26 may have a substantiallycylindrical shape that is suitable for being journalled in a bearing forrotation with respect to the bearing.

At least a portion of the roll body 18 may be electrically conductive orable to carry an electrical current. The conductive portion may belocated on the body such that the portion is likely to be the firstportion of the roll that contacts the other roll when the rolls aremoved toward each other from a spaced condition. Illustratively, atleast a portion of the circumferential surface 22 of the body 18 may beelectrically conductive, and at least some of the teeth may beelectrically conductive. Typically, although not necessarily, theelectrically conductive portion of the circumferential surface is formedof a conductive metal such as steel.

In the illustrative embodiments of the system 10, one of the rolls maybe a stationary roll which is mounted to the frame 12 in a manner suchthat the stationary roll is substantially immovable with respect to theframe during normal use of the system, and the other one of the rolls isa movable roll which is mounted on the frame in a manner that permitsmovement of the movable roll with respect to the stationary roll.Although this is the preferred configuration for the purpose of greatersimplicity, both of the rolls may be mounted on the frame in a mannerthat permits both rolls to move with respect to the frame. The movableroll is thus movable with respect to the frame, but is also movable withrespect to the stationary roll such that the movable roll is able tomove toward and away from the stationary roll to adjust a size andcharacter of a separation gap 27 between the rolls. In some embodiments,the movable roll may be mounted on the frame 12 in a manner that permitsindependent movement of the ends 20, 21 with respect to the stationaryroll, and also with respect to the frame, so that the magnitude of theseparation gap may vary between the ends. In the illustrativeembodiments of this description, the first roll 14 forms the movableroll and the second roll 16 forms the stationary roll.

The system may also include one or more roll supports, with each rollsupport receiving one of the end portions 28 of one of the roll shafts14, 16 to thereby support the respective roll body on the frame in theindicated manner (e.g., movable or stationary). Each of the rollsupports may include a bearing or other suitable structure forsupporting a portion of a rotating shaft. The roll supports may includeat least one movable roll support assembly 30 for supporting the rollshaft of the movable roll on the frame, and in embodiments a pair ofmovable roll support assemblies 30, 31 may be employed with eachassembly supporting one of the end portions 28 of the roll shaft of themovable roll 14. The movable roll support assemblies 30, 31 may bemovably mounted on the frame to permit movement of the movable rolltoward and away from the stationary roll to thereby change and adjustthe size of the separation gap 27 between the rolls 14, 16.

Illustratively, each of the movable roll support assemblies 30, 31 mayinclude a bearing block 32 which is movably mounted on the frame, andmay be slidably mounted on the frame by one or more guides 34 mounted onthe frame that effectively form a track for the bearing block to movetoward and away from the stationary roll 16. The movable roll supportassemblies 30, 31 may also include an adjustment structure 36 which isconfigured to adjust a position of the bearing block with respect to thestationary roll 16 and also with respect to the frame 12. Anillustrative adjustment structure includes a stop 38 mounted on theframe 12, a brace 40 mounted on the bearing block 32, and an adjustmentmember 40 which is configured to move the brace with respect to thestop, and thereby move the bearing block with respect to the frame. Aportion of the exterior of the adjustment member 42 may be threaded, andthe threaded portion of the adjustment member may extend through athreaded hole in the brace 40 such that rotation of the adjustmentmember in a first rotational direction moves the brace toward the stop38 and rotation of the adjustment member in a second rotationaldirection moves the brace away from the stop.

Each of the movable roll support assemblies 30, 31 may also include abiasing structure 44 which is configured to bias movement of the movableroll toward or away from the stationary roll 16, and may accomplish thisthrough biasing the bearing block 32 toward or away from the roll 16.Illustratively, the biasing structure 44 may comprise a spring which ispositioned between the stop 38 and the brace 40 to push the brace awayfrom the stop and thereby urge the bearing block to move toward thestationary roll subject to the adjustment by the adjustment member 42.

The roll supports may also include a stationary roll support 46 forsupporting the roll shaft 26 of the stationary roll 16. A pair of thestationary roll supports 46 may be employed to support the opposite endportions of the roll shaft, and may each comprise a bearing mounted onthe frame in a manner that is configured to hold the stationary roll 16in a fixed position on the frame during normal operation of the system,such as by being directly bolted to the frame.

The system 10 may also include an electrical isolation assembly which isconfigured to electrically isolate or insulate at least one of the rolls14, 16 from the frame, and may be employed to isolate both of the rolls14, 16 from the frame. In some embodiments, the isolation assemblyisolates the roll support that is supporting the isolated roll from theframe to thereby prevent an electrical current to travel between theframe and the roll support or the roll supported by the roll support.Illustratively, the electrical isolation assembly may comprise aninsulating pad 48 which is configured to be positioned between the rollsupport for the isolated roll and the frame 12 to thereby electricallyisolate the roll support from the frame by virtue of the insulating padbeing positioned between the roll support and the frame. The electricalisolation assembly may also include at least one insulating sleeve 50which is positioned over at least one fastener employed to mount theroll support to the frame, and is preferably positioned over each of themounting fasteners employed to mount the roll support on the frame. Theinsulating sleeve 50 may be configured so that the shaft of the mountingfastener as well as any head or nut on the fastener is also electricallyisolated from contact with the roll support. The insulating pad 48 andthe insulating sleeve 50 may be formed from an electricallynon-conductive material such as a plastic or composite.

The system 10 may also include a detection apparatus 52 which isconfigured to detect contact between the rolls, and the detectionapparatus may be configured to detect a change in electrical potentialof at least one of the rolls which may result from contact between therolls. The detection apparatus 52 may comprise a power source 54 whichis configured to provide an electrical potential, and the power sourcemay comprise a battery or the electrical service of a building suppliedby a electrical utility. The detection apparatus 52 may also include aconnection structure 56 which is configured to connect the power source54 to the first roll 14. The connection structure 56 may include a firstor connection conductor 57 which electrically connects the power source54 to the first roll. The first conductor 57 may be connected to theroll support for the first roll, and illustratively may be electricallyconnected to the movable roll support assembly 30 for the first roll.For example, the first conductor 57 may be electrically connected to thebearing block 32 on which one of the end portions of the roll 14 ismounted. Usually the first conductor 57 may only need to be connected toone movable roll support assembly supporting one end portion of the rollshaft, particularly if the roll shaft is formed of an electricallyconductive material such as steel. Conduction of electricity along anelectrical path from the end portion of the roll shaft, through the rollshaft and through the roll body (or at least a portion thereof) to theconductive portion or portions of the circumferential surface 22 of theroll 14 effectively provides an electrical path between the connectionstructure 56 and the conductive portion of the surface.

The detection apparatus 52 may also include a reception structure 58which is configured to connect the power source to the second roll 16such that contact between the first 14 and second 16 rolls creates acomplete electrical circuit through the rolls and to the terminals ofthe power source. The reception structure 58 may comprise a second orreception conductor 59 which may be electrically connected to the secondroll support such as by a wire connected to the roll support. Anelectrical path may be formed between the roll support through the endportion of the roll shaft and roll body of the roll 16 to the conductiveportion of the circumferential surface of the roll 16.

As the location of the rolls in the system 10 may be considered to behazardous due to the presence of dust and fine particles, and thereforethe circuit may utilize a limited current and voltage and may not permitany surge or accidental wire connection possibly allowing for a shortcircuit. An intrinsically safe barrier may be used on the input andoutput sides of the circuit. An illustrative circuit may utilize avoltage of less than 12 VDC and may limit current to less than 10 mA.

The system 10 may also include a signaling apparatus 60 which isconfigured to produce a signal that indicates that a change in theelectrical potential of at least one of the rolls is detected, such asthrough the flow of current through the rolls resulting from contactbetween the rolls. The signaling apparatus 60 may be an element in thecircuit formed by the power source 54, the connection structure 56, therolls 14, 16, and the reception structure 58 such that a current flowingthrough the rolls is also caused to flow through the signalingapparatus.

The signaling apparatus 60 may be configured to produce a perceptiblesignal which is perceptible by one of the senses of a human being (e.g.,visual, audible, or tactile) and/or may produce a signal in a digital oranalog form that is able to be transmitted to a device able to receiveand be triggered in some manner by the signal. The signaling apparatus60 may be configured to produce a visually-perceptible signal orindicator such as a light emitting device (e.g., a bulb or LED) thatilluminates to provide the visually-perceptible signal. The signalingapparatus may also comprise an audibly-perceptible signal or indicatorthat is able to be heard by an operator (e.g., a horn or buzzer orbell). The signaling apparatus may include an indicator that produces atactilely-perceptible indicator such as a vibration or other form ofmovement that may be picked up by the touching of the skin to a surfaceor control. The types of signals described are not mutually exclusiveand may be used in combination with each other.

The signal may also be in the form of a current or change in voltagepotential that is provided to a logic element such as a programmablelogic controller, processor, analog to digital converter, or otherdevice that converts or processes the signal to a suitable form forcontrol circuitry configured to act upon the detection of contact of therolls.

Apparatus that may utilize the signal may include an automatedadjustment apparatus that operates or causes the system to automaticallyadjust the position of the movable roll to a desired separation gapdistance from the stationary roll intended to produce a ground materialof a particular character. For example, as illustratively shown in FIG.11, the signaling apparatus 60 may form a detector that generates asignal to a controller 62 that is indicative of the position of therolls with respect to each other, such as whether the rolls are incontact with each other in the zero location or not. This signal may beused by the controller 62 to move one of the rolls through therespective roll support toward the other roll (and thus toward the zerolocation for the roll) or away from the zero location toward anoperational location of the roll which corresponds to a desiredseparation gap. The controller 62 may signal an actuator 64 to operatethe roll support to move the roll, and illustratively the actuator maybe a motor that rotates a threaded rod to move the roll support althoughother types of actuators may be employed. The desired separation gap maybe signaled to the controller 62 in any suitable manner, such as amanual input panel 66 or a computer processor. Significantly thestructure and circuitry depicted in FIG. 11 may be utilized on each sideof the apparatus and the respective roll ends of the apparatus, suchthat each of the ends of the movable roll of the pair of rolls isindependently movable in an automated manner.

In operation, the adjustment apparatus may cause the movable roll tomove toward the other roll, and when a signal is received from thesignaling apparatus that contact between the rolls has occurred, theadjustment apparatus may discontinue or stop the movement of the rolland the zero location recorded, The movement of the roll may beconducted using actuators 64 for both roll supports or may be conductedusing only one actuator acting on one roll support (and thus one end ofthe roll) at a time, with the zero point for one end being detectedfirst and the other end being detected after the one end. The adjustmentassembly may cause the actuators to back the one (first) end of themoving roll away from the stationary roll before the other (second) endis moved toward the stationary roll. Once the zero location, or zeropoints, of the roll being adjusted have been determined, then theadjustment assembly may use that zero point data to move the ends of therolls (through the respective actuators) to the appropriate adjustmentpoint to create the desired separation gap.

Another aspect of the disclosure relates to a method of positioning aroll with respect to another roll in a system, such as a processing orgrinding or milling apparatus. The method may include providing a systemhaving some or all of the elements and features set forth in thisdisclosure, and applying an electrical potential to a first one of therolls, such as by connecting the first roll to a terminal of anelectrical power source, and electrically connecting a second one of therolls to another terminal of the power source. The method may alsoinclude moving a movable one of the rolls toward a stationary one of therolls, and may include moving a first one of the ends of the movableroll toward a first one of the ends of the stationary roll. A furtheraspect of the method may include detecting a change in the electricalpotential in the second one of the rolls and/or detecting an electricalcurrent flow from the first roll to the second roll, and producing asignal when a change in the electrical potential of the second roll, ora current flow, is detected. The method may further includediscontinuing movement of the movable roll toward the stationary rollupon the detection, such as discontinuing movement of the first end ofthe movable roll toward the first end of the stationary roll, anddetermining a zero point for the first end of the movable roll when thechange in electrical potential or current is detected. The method mayalso include moving a second one of the ends of the movable roll towarda second one of the ends of the stationary roll, detecting a change inthe electrical potential in the second roll and/or detecting anelectrical current flow from the first roll to the second roll, andproducing a signal when a change in the electrical potential of thesecond roll, or a current flow, is detected. The method may furtherinclude discontinuing movement of the movable roll toward the stationaryroll upon the detection, such as discontinuing movement of the secondend of the movable roll toward the second end of the stationary roll,and determining a zero point for the second end of the movable roll whenthe change in electrical potential or current is detected.

It should be appreciated that in the foregoing description and appendedclaims, that the terms “substantially” and “approximately,” when used tomodify another term, mean “for the most part” or “being largely but notwholly or completely that which is specified” by the modified term.

It should also be appreciated from the foregoing description that,except when mutually exclusive, the features of the various embodimentsdescribed herein may be combined with features of other embodiments asdesired while remaining within the intended scope of the disclosure.

Further, those skilled in the art will appreciate that the stepsdisclosed in the text and/or the drawing figures may be altered in avariety of ways. For example, the order of the steps may be rearranged,substeps may be performed in parallel, shown steps may be omitted, orother steps may be included, etc.

With respect to the above description then, it is to be realized thatthe optimum dimensional relationships for the parts of the disclosedembodiments and implementations, to include variations in size,materials, shape, form, function and manner of operation, assembly anduse, are deemed readily apparent and obvious to one skilled in the artin light of the foregoing disclosure, and all equivalent relationshipsto those illustrated in the drawings and described in the specificationare intended to be encompassed by the present disclosure.

Therefore, the foregoing is considered as illustrative only of theprinciples of the disclosure. Further, since numerous modifications andchanges will readily occur to those skilled in the art, it is notdesired to limit the disclosed subject matter to the exact constructionand operation shown and described, and accordingly, all suitablemodifications and equivalents may be resorted to that fall within thescope of the claims.

1. A system comprising: a frame; a pair of rolls, the rolls including afirst roll and a second roll, each of the rolls having a circumferentialsurface, a plurality of teeth being formed on the circumferentialsurface, at least a portion of the circumferential surface beingelectrically conductive; roll supports configured to support the rollson the frame in a manner such that at least one of the rolls is movableto adjust a separation gap between the rolls; a detection apparatusconfigured to detect contact between the rolls; a signaling apparatusconfigured to produce a signal when the detection apparatus detectscontact between the rolls; and an adjustment apparatus configured toreceive the signal from the signaling apparatus and change movement ofone of the rolls with respect to the other of the rolls.
 2. The systemof claim 1 wherein one of the rolls is a stationary roll mounted on theframe in a manner that is substantially immovable with respect to theframe and wherein one of the rolls is a movable roll mounted on theframe in a manner permitting movement of the movable roll with respectto the stationary roll.
 3. The system of claim 1 wherein the adjustmentapparatus includes an actuator configured to operate one of the rollsupports to move the roll supported by the roll support with respect tothe other roll.
 4. The system of claim 3 wherein a pair of the actuatorsare configured to operate the roll supports for a said roll individuallyof each other to move ends of the rolls independently of each other. 5.The system of claim 1 wherein the adjustment assembly is configured toterminate movement of the one of the rolls upon receipt of the signalfrom the signaling apparatus.
 6. The system of claim 1 wherein theadjustment apparatus is configured to produce movement of the one of therolls.
 7. The system of claim 1 wherein the signaling apparatus isconfigured to produce a signal in a digital or analog electrical form.8. The system of claim 1 wherein the detection apparatus is configuredto provide an electrical potential to one of the rolls.
 9. The system ofclaim 8 wherein the detection apparatus is configured to detect a changein the electrical potential of at least one of the rolls resulting fromcontact between the rolls.
 10. The system of claim 8 wherein thedetection apparatus comprises a power source configured to provide anelectrical potential, a connection structure configured to connect thepower source to the first roll, and a reception structure configured toconnect the power source to the second roll such that contact betweenthe first and second rolls creates a complete electrical circuit. 11.The system of claim 10 wherein the signaling apparatus forms a part of acircuit with the power source, the connection structure, the first roll,the second roll and the reception structure.
 12. The system of claim 10wherein the signaling apparatus is configured to signal when a change inelectrical potential is detected by the detection apparatus.
 13. Thesystem of claim 1 wherein the detection apparatus is configured todetect contact of one roll with the other roll while at least one of therolls is rotating.
 14. A system for grinding grain material, the systemcomprising: a frame; a pair of rolls mounted on the frame to rotateabout substantially horizontal axes and being, the rolls including afirst roll and a second roll, each of the rolls having a circumferentialsurface, a plurality of teeth being formed on the circumferentialsurface, at least a portion of the circumferential surface beingelectrically conductive; roll supports mounted on the frame andconfigured to support the rolls on the frame in a manner such that atleast one of the rolls is movable to adjust a separation gap between therolls, the rolls being rotatable about substantially horizontal axeswith a gap therebetween measured in a substantially horizontal plane,and being adjustable in a substantially horizontal direction to adjust amagnitude of a horizontal separation gap through which grain materialfalls substantially vertically between the rolls; a detection apparatusconfigured to detect contact of one of the rolls with an other one ofthe rolls, the detection apparatus being configured to provide anelectrical potential to at least one of the rolls such that contact ofsaid one roll with said other roll causes a change in the electricalpotential of at least one of the rolls; a signaling apparatus configuredto produce a signal when the detection apparatus detects a change in theelectrical potential of one of the rolls indicating contact between therolls; and an adjustment apparatus configured to receive the signal fromthe signaling apparatus and change movement of one of the rolls withrespect to the other of the rolls.
 15. The system of claim 14 whereinthe detection apparatus comprises a power source configured to providean electrical potential, a connection structure configured to connectthe power source to the first roll, and a reception structure configuredto connect the power source to the second roll such that contact betweenthe first and second rolls creates a complete electrical circuit. 16.The system of claim 15 wherein the signaling apparatus forms a part of acircuit with the power source, the connection structure, the first roll,the second roll and the reception structure.
 17. The system of claim 15wherein the signaling apparatus is configured to signal when a change inelectrical potential is detected by the detection apparatus.